Treatment Recommendations for Pediatric Myocarditis
For pediatric myocarditis, a stepwise approach is recommended with intravenous immunoglobulin (IVIG) and/or glucocorticoids as first-line therapy, followed by mechanical circulatory support for severe cases unresponsive to medical management.
Diagnostic Approach
- Cardiac evaluation is essential in all suspected cases, regardless of presenting symptoms, including ECG, echocardiography, and cardiac biomarkers (BNP, troponin) 1
- Sequential monitoring of inflammatory markers, BNP/NT-proBNP, and troponin T levels helps guide treatment decisions 1
- Cardiac magnetic resonance imaging (CMR) has emerged as an important non-invasive diagnostic tool, particularly when using the revised Lake Louise Criteria 2
- If myocarditis is suspected, consider evaluating nasal swab and stool for viruses, as well as blood polymerase chain reaction 1
- In patients who do not recover, endomyocardial biopsy (EMB) may be considered to guide further therapy 1
Initial Management
- Hospital admission is recommended for all suspected cases of myocarditis to monitor for rapid progression of cardiac involvement 1
- First-tier immunomodulatory treatment includes:
- Before administering IVIG, assess cardiac function and fluid status to avoid volume overload; consider slower infusion rates or divided doses over 2 days if cardiac function is compromised 1
- Guideline-directed heart failure therapy should be implemented, including diuretics, beta-blockers, and ACE inhibitors as appropriate 1
Management of Severe Cases
- For severe acute heart failure from myocarditis, mechanical assist devices and extracorporeal membrane oxygenation (ECMO) are beneficial as a bridge to recovery or heart transplantation 1, 3
- Pre-cardiac arrest use of ECMO may be beneficial in children with acute fulminant myocarditis 1
- Heart transplantation is recommended for children with severe end-stage heart failure refractory to treatment 1
- In cases of suspected immune checkpoint inhibitor-associated myocarditis, high-dose corticosteroids (1 mg/kg methylprednisolone IV) should be administered until improvement to grade ≤1, followed by at least 4-5 weeks of tapering doses 1
Special Considerations
- Anti-inflammatory therapy with steroids alone (without IVIG) is not beneficial in pediatric myocarditis according to available evidence 1
- In cases of myocarditis associated with multisystem inflammatory syndrome in children (MIS-C), a more aggressive immunomodulatory approach may be needed 1
- Mechanical circulatory support shows better outcomes in the absence of viral infection and myocardial inflammation 3
- Immunosuppression with cyclosporine and prednisone may be considered in specific cases, as some studies show improved long-term survival rates 4
Follow-up Care
- Repeat echocardiograms should be obtained at 7-14 days and 4-6 weeks after initial presentation 1
- For patients with left ventricular dysfunction, cardiac magnetic resonance imaging at 2-6 months post-acute illness allows evaluation of fibrosis and scarring 1
- EKGs should be obtained every 48 hours during hospitalization and at each follow-up visit to monitor for conduction abnormalities 1
- Holter monitoring may be needed at clinical follow-up if conduction abnormalities are present 1
- Coordination of care across providers is essential for optimal management of these complex cases 1
Prognostic Factors
- Viral presence detected by PCR is associated with worse outcomes (death or need for transplantation) 3
- Absence of viral infection and lack of myocardial inflammation are associated with better recovery rates 3
- Children with acute fulminant myocarditis have a 75% survival rate with appropriate mechanical circulatory support 3
The management of pediatric myocarditis requires a multidisciplinary approach involving cardiologists, intensivists, and infectious disease specialists to optimize outcomes and reduce mortality and morbidity.